<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        .demo{
            width: 100px;
            height: 100px;
            background-color: #ff5628;
            display: none;
        }
    </style>
</head>
<body>
<input type="button" value="按钮" id="btn">
<div class="demo"></div>
<script src="../jquery-1.12.4.js"></script>
<script>
    $(function () {
        var flag = false;
        $("#btn").on("click",function () {
            if(!flag){
                flag = true;
                //delay  延迟执行，毫秒
                $(".demo").stop().slideDown(1000).delay(1500).slideUp(1000,function () {
                    flag = false;
                });
            }

        })
    })
</script>
</body>
</html>